Help concerning upgrading my computer

Well I have an older desktop computer and was hoping to upgrade as I'm not really intrested in buying a whole new computer here are the products I was wondering about:
www.newegg.com/Product/Produ...N82E16813138266[/url]
www.newegg.com/Product/Produ...N82E16814127176[/url]
www.newegg.com/Product/Produ...N82E16813138269[/url]
What I'am not aware of is if all of these are compatible and what the result would be. Would this turn out to be a good computer with some ram like a Gigabyte or so and would I be able to play new games at a satisfactory quality. Also what is the x800 equal too in nvidia cards like is it equal to a 6800 ultra? Just wondering. And which mobo should I choose as well as what is the most cost effective amd processor I can get with it that can still run all the games I want? Lastly has anyone here worked with newegg I live in Canada so I kinda need to know about tax/shipping and also is there a Canadian website that is somewhat like newegg since it would be more convient to work with them. Thankyou.